#pragma once
#include<stdlib.h>
#include<iostream>
using namespace std;

struct Stack
{
	int* a;
	int size;
	int capacity;
	//...
};

void StackInit(struct Stack* ps, int n = 4);
void StackPush(struct Stack* ps, int x);

void f(int a, char b);
void f(char b, int a);
